Switch for controlling electric circuits



May 5, 1925.

W. J. PRITCHETT SWITCH FOR CONTROLLING ELECTRIC CIRCUITS Filed Sept. 3, 1921 Patented May 5, 1925.

UNITED STATES PATENT OFFICE.

SWITCH FOR CONTROLLING ELECTRIC CIRCUITS.

Application filed September 3, 1921.

To all whom it may concern:

Be it known that WILLIAM Jncon PRITOHETT, a subject of the King of Great Britain and Ireland, residing at 47 Circular Quay East, Sydney, in the State of New South \Vales, Commonwealth of Australia, has invented certain new and useful Improvements in Switches for Controlling Electric Circuits, of which the following is a specification.

This invention relates to improvements in switches for controlling electric circuits and the object of the invention is to provide an improved switch or circuit breaker which is simple in construction, quick and positive in action, easily and safely manipulated, and cheap to manufacture.

A further object of the invention is to provide a simple fuse attachment whereby the additional cost of providing separate fuse fittings is obviated.

The invention comprises an insulating base plate having vertically disposed parallel cheeks or brackets between which is pivoted a pair of spring controlled lever arms in longitudinal alignment and adapted to be oscillated to make and break the circuit by the vertical manipulation of an in termediate operating handle. Each contact maker being bridged by a fuse wire.

But in order that the invention may be clearly understood reference will now be made to the drawings which illustrate the invention and in which Figure 1 is a perspective view with the cover partially broken away.

Figure 2 is a longitudinal section.

Figure 3 is a sectional plan with the cover removed.

The base plate a which is constructed of insulating material such as porcelain or the like has vertically disposed parallel checks or brackets A between which is pivoted a pair of lever arms B, by means of trunnions 5 that take in slots 6 in brackets A. The lever arms B which are constructed of in sulating material and which may be either round or square in cross section are bored to receive a spring 7 and movable rod 8. The free end of the rods 8 each take into opposing cavities 9 in the opposite walls of an intermediate vertically disposed operating handle 10 which is adapted to slide in grooves 11 in inner walls of brackets A.

Serial- No. 498,458.

When the lever arms B are assembled the rod 8 compresses the spring 7 and the cavities 9 are so positioned in the operating handle 10 as to always hold the arms B in an oblique position at the extremity of its movement either up or down as illustrated in Figure 2. At the free end of each of the arms B is a cross member 12 which has contact points 18 at each end, these contact points overlie corresponding fixed contacts 14 in base plate 4. The contacts 13 on the ends of cross pieces 12 are bridged by a fuse wire 15 which is secured thereto by screws 16.

In operation the circuit is closed by raising the operating handle 10 as shown in full lines Figure 2, and broken by depressing same as shown in Figure 1.

The parts are protected by a cover 17 through the top of which the operating handle 10 passes.

1. A switch for controlling electric circuits comprising a base of non-conducting material, parallel brackets on said base, a pair of obliquely positioned spring cushioned telescopic lever contact arms pivoted and movable between sa d brackets and hav ing cross members with separate contacts, fuse wires bridging said contacts, contacts and terminals on said base and an intermediate operating handle for oscillating the contact arms into and out of engagement with the contacts.

2. A switch for controlling electric circuits comprising an insulating base, parallel b 'ackets on said base, a pair of hollow lever arms pivotally mounted between the brackets, compression springs within the lever arms, rods movable in said lever arms for compressing the springs, an intermediate operating handle to which the rods are connected, cross members for the lever arms having separated contact points electrically connected by fuse wires, and separated contacts and terminals on the insulating base opposed to the contacts of the cross members.

In testimony whereof he has affixed his signature in presence of two witnesses.

W'ILLIAM JACOB PRITGHETT. lVitnesscs T. O. ALLEN, Jr., G. GARDNER. 

